cannon firing priority

[MizInIA]

it seems to me that the cannons firing on creeper shoot at creeper on the same terrain level in range before moving to closer creeper on a lower terrain level. is this true and/or is there a weight applied to terrain difference?

just wanted to find out if my mind is playing tricks on me...

[Grauniad]

Tthe algorithm is designed to keep the adjacent surface clear to allow other units to be on that surface. Consider the narrow scenario of a bridge 2 units wide. Would you rather have the cannon fire at the deeper creeper right along itself, but a level below what it is on, or try to keep the adjacent portion of the bridge clear?  As soon as the adjacent creeper is high enough to overrun, it will be targeted.

[MizInIA]

cool. I am hoppy with the targeting priority. I just was expecting it to be the same as CW1 and CW2 so was supprised when it seemed to be playing tricks on me.  :)